In late July, a €40 million, 9000-m² test facility in Friedrichshafen, MTU’s lead site and main R&D location, officially went into service. The new five-story test facility “was already at the planning stage before Rolls-Royce became sole owner of [MTU] and before we began intensive cooperation with other R&D units at Rolls-Royce. [Construction] began in spring 2013, and Rolls-Royce obviously supported this investment,” according to a company spokesman. “Since then, our operations have become fully integrated into the R&D activities of Rolls-Royce, and we both benefit from that collaboration.”
Rolls-Royce has two main business divisions, Aerospace and Land & Sea, that latter of which comprises Marine, Nuclear, and Power Systems. MTU, MTU Onsite Energy, Bergen Engines, and L’Orange are all part of Rolls-Royce Power Systems (RRPS). Of the 15,500 engineers that Rolls-Royce employs globally, about 1600 work in the Power Systems segment.
MTU has R&D test stands that are similarly equipped in its Aiken, SC, plant, and RRPS has over 100 test stands in service all over the world used for R&D, series production, and repairs and engine overhauls.
“This facility supplements existing capacities with new measuring and analysis technologies,” Werner Hussal, Head of Test Stand Planning, RRPS, told SAE Magazines. “Our test stands are manned by experienced engineers, researchers, and technicians. For the new facility, certain staff have received targeted training to familiarize them with the new technologies and teach them to make the most of the potential that the systems offer.”
The company stresses that it intends to use the new facility not only to test further developments on existing engines, but to break into new territories, with one such new territory being R&D into a gas engine for mobile applications.
Gas engines used continuously in stationary applications such as in MTU Onsite Energy's combined heat and power modules are a proven technology. RRPS is now looking to develop a gas engine for use in ships, said the spokesman. This is a major challenge because the gas engine must not only be ecologically sound but offer as many of the advantages as possible as conventional diesel engines.
In this first phase of the facility, three stands for testing 2500-kW engines were set up. Construction is currently underway for a gas supply network for the gas engine research that is to go into service in mid-2016. Additional test stands can also be installed as future programs are identified.
For now though, the focus on meeting emissions standards is clear, and MTU believes that future emissions standards are going to be another tough technological challenge that will force it to think in terms of bigger systems, and systems integration. “For example, the way the engine interacts with the exhaust aftertreatment can be extremely complex,” said the spokesman. “Exhaust gas aftertreatment is one of five key technologies on which we focus very closely. We develop our own exhaust aftertreatment systems so that they can be perfectly tuned to our engines and their applications. We work closely with leading catalyzer and component manufacturers so that we can provide our customers a complete systems package from one source that has been qualified in-house. Developing exhaust aftertreatment systems that optimally meet the needs of its customers is one of the main missions of the new test facility.”
Even in this day and age of ever-increasing sophisticated simulation and virtual design tools, brick-and-mortar test facilities are as important as ever. “Equipment for the analytical configuration and simulation of the thermo-dynamic processes that take place in an engine are essential tools for effective R&D, especially when it comes to large diesel engines. However, these are mathematical tools that can be used to back up high-level real-life testing, but not replace it,” said Hussal.
“By simulating components and processes, we can limit the number of time-consuming and expensive test runs we carry out and clearly demarcate test scopes in advance. But the intricacies of a highly complex process, such as, for example, the interaction between the engine and a specific exhaust aftertreatment system, can only be reproduced using simulation to a limited extent. A real-life test run helps us to verify and perfect the results of our simulations. Simulation and real-life testing go hand-in-hand.”
To highlight correlations from anything between two and eight parameters, and all the associated interactions, MTU uses DOE (design-of-experiment) methods in connection with model-based optimization. That way, the company minimizes test run expenditure and maximize our information gain.
“During the test runs, we only vary those performance and emissions-relevant parameters that were revealed as significant in simulations. This can be done automatically at the test stand,” said Hussal. “The results we then receive are mathematical models that describe engine behavior (e.g., emissions, consumption, etc.) as a function of the various input values. So in the engine test, a large number of parameter variations can be implemented very efficiently within a short space of time. In the model-based optimization that follows, we calibrate the engine optimally to achieve the desired levels of emissions and consumption according to specific ambient conditions.”
A special feature of the new testing facility is what MTU refers to as a “gallery” that has been built above each test stand booth. “The gallery is a special platform above the engine that can carry its exhaust aftertreatment systems, such as SCR for reducing nitrates. These systems are often very bulky, and we did not have enough space for them on our existing test stands,” said Hussal. “We now have enough space to set up close-to-reality testing and measurement scenarios using high-tech measurement paths and calming sections.”
He added that another feature of the new building is a set-up hall outside the actual test stand area. It is there that engineers will build the test configurations on mobile platforms, keeping the time needed for preparations at the test stand itself to a minimum and improving operational efficiency.
Rolls-Royce does not split out its R&D spending by division, but the majority of that money is currently invested in Aerospace, mainly because the investment cycles are longer and more costly than they are in (non-nuclear) Land & Sea operations. That said, the spokesman estimated that in 2014 its R&D spend for gas turbines was ~£1 billion, and for reciprocating engines (MTU and Bergen Engines) ~ £150 million.
Wherever the R&D investment money goes, Rolls-Royce has in place internal systems and processes that allow its engineers to share ideas and look for innovative solutions to common problems. Engineers in one part of the business are able to pose challenges that other areas of the business can comment on and suggest solutions for. For example, knowledge of material science from its aerospace division has enabled it to develop new seals for marine, while automated manufacturing technology developed for marine propeller surface finishing is now being applied to aerospace fan blades.